The advance of mobile computing has resulted in unprecedented levels of access to information. A significant number of people use mobile computing devices on a daily basis to communicate with others, navigate the physical world, conduct business, and access information, as well as to provide entertainment and personal assistance. While mobile computing devices tend to be deliberately compact to promote portability, the relatively small display sizes on these devices may diminish the user experience in a number of ways. For instance, it is notoriously more difficult to provide user input to mobile computing devices using tiny keypads and touch-sensitive displays than it is to provide user input to a desktop computing device using a full-sized keyboard and mouse.
Small displays can also diminish the viewing experience for a user who wishes to use the mobile computing device to watch content, such as television, movies, and video clips, for example. On the other hand, large display devices in public places enable a rich visual experience but are often muted to avoid disturbing those who are not interested in listening to the displayed content. Such displays may also be muted if there are several displays in the same location providing different content. Large displays in public spaces may use closed captioning or subtitling to give users a visual rendering that represents a transcription, verbatim or edited, of the audio portion of content being shown on the display. Closed captions, however, are visually distracting and fail to provide the user with a fully satisfying experience as rich auditory features, such as music and voice inflection cannot be satisfactorily rendered via text.